Experts believe doing so would both increase protection against cervical cancer in girls through “herd immunity”, but also protect against mouth and throat cancers in both sexes.

Yesterday the Joint Committee on Vaccination and Immunisation (JCVI), which advises the Department of Health, formally recommended the HPV injection should be offered to all teenagers.

A spokesman said: "If considering a cost-effectiveness analysis where a combined girls' and boys' programme is compared to no vaccination, gender-neutral HPV vaccination is highly likely to be cost-effective."

The announcement follows an apparent u-turn by the committee, whose interim report last year indicated the vaccine would not be recommended for boys.

Professor Helen Stokes-Lampard, chairwoman of the Royal College of GPs, said: "The HPV vaccine has proven extremely effective in protecting women against cervical cancer and we now have strong evidence to demonstrate that the vaccine also provides protection against a number of other serious cancers which affect both men and women, including head and neck cancer and anal cancer.

"It has been frustrating that this effective vaccine has, until now, only been available on the NHS to girls but not boys. We hope parents will take up this important opportunity to get their sons and daughters vaccinated as soon as it is available to them."